I don't mind someone (my DD, usually) tattling if she gets hit or if someone is hurting themselves or someone else. What drives me nuts is the tattling about stupid stuff, like "she looked at me funny" or "she won't let me have a turn" or "she said she's not my friend" or "she took her shoes off" or "she said she's older than me", etc and so on...I usually tell my DD that she needs to learn to work it out with her friends and usually I am close by and hear the whole exchange anyway...I guess what bugs me about it is that it is often just an "attention getter" and she tries to see how many times she can interrupt me in one conversation!